Initial results show that mean of the Probability Density Function (PDF) for BT Vmax estimates from tropical storm to CAT4 hurricanes exceeds that from the SFMR Vmax distribution by 6 m/s, representing a 12-15%, or one storm category, overestimate. BT and SFMR Vmax estimates show close agreement for CAT5 storms. The issue of under sampling of SFMR Vmax due to flight tracks missing the true Vmax is addressed using two years of processed airborne Doppler radar data. Anew pressure-wind relationship derived using SFMR data shows a similar offset compared to BT pressure-wind relations used by forecasters.
Initial results show that the ADT derived Vmax tends to be an overestimate for weak CAT1 and CAT2 storms while underestimating CAT 4 storms. There is a bimodal distribution of ADT Vmax estimates with more CAT 1 and CAT 3/4 storms than indicated by SFMR Vmax and fewer ADT CAT2 storms than indicated by SFMR Vmax. This suggests that ADT may have trouble accurately identifying the eye feature as it is first appearing and transitioning storms from CAT 1 to CAT 3 intensity too quickly. Preliminary comparisons with conventional Dvorak technique Vmax estimates suggest that this effect is less pronounced. The present study suggests the possibility of reducing the uncertainty in tropical cyclone maximum surface wind estimates to the level of scatter in the SFMR vs GPS dropsonde comparisons by tuning future Best Track and satellite based ADT surface maximum wind estimates to those produced by SFMR surface wind measurements.
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